Usually a family member will take on the role of a trustee and guardian for an adult who lacks capacity. The choice of who is best for that role depends on several factors including age and place of residence.
The estate of the adult for whom the order is made is responsible for payment of the costs of the application. If that adult is of very limited means, the government will pay a small amount for the legal fees.
The first step is to obtain an assessment of capacity by a physician who is qualified to provide the type of opinion required. The assessment must be in a particular form. There are a number of other documents which must be prepared in the correct format and submitted to the Office of the Public Guardian which in turns files them with the Court. A lawyer who is experienced in this area can guide you through the process, prepare and file the documents, and advise you regarding the options available for your particular case.